1. Field of the Invention
This invention relates to a plasma processing device and plasma processing method thereof, and particularly to a plasma processing device having the upper plate and the lower plate and plasma processing method thereof.
2. Description of the Prior Art
The plasma has already been widely applied to various fields, such as the semiconductor integrated circuit industry. The growth of film from different material and the etching of circuit are achieved by the plasma technology generally. In addition, as for the semiconductor packaging, the plasma is used to wash and change the material surface, in order to achieve special function and effect.
As for an example, the plasma processing device is used for washing the chip. Conventionally, a great amount of water is required for washing the chip in the semiconductor process. The semiconductor process moves towards the miniaturized process gradually. The requirement for the cleanliness of chip itself is raised constantly. Accompany with deeper and longer groove on the chip, the wet etching is hard to be used because of its congenital shortcoming. The dry etching has become better solution at present gradually.
The plasma processing device can be used for dry cleaning. The plasma cleaning principle is similar to the plasma etching. The high frequency power is provided by the electrode to ionize the gas into the plasma. This plasma impacts the chip surface to remove the polluted particles from its surface, and then achieves the goal of cleaning. Similarly, this plasma can also etch or film the chip surface for pretreatment. The above-mentioned plasma has been applied to the process of IC packaging and the liquid crystal module widely at present.
However, the plasma itself has relatively high destruction ability, which is apt to damage the chip or chip surface in cleaning process. Therefore, as for the example of common downstream plasma device and remote plasma device, the improvement way is to increase the distance between the chip and the plasma, in order to reduce the destruction of chip surface by the plasma directly.
The integrated circuit has already been developed to the complicated device gradually. The advancement of chip design needs faster circuit system and more intensive circuit density. Because the speed of circuit and number of executable function will increase with the density of circuit structure, the circuit density will play an important role. The factors affecting the speed of integrated circuit and the design characteristics of circuit density include the resistance and thickness of material. This material is used to form the circuit structure layer on the substrate.
The metal material is applied to design the circuit structure, such as similar structure, such as the metal line, channel, and electrode etc. The metal structure is very important to the function of integrated circuit. The material with low resistance coefficient has good ability to inhibit the permeation of poly-silicon. This makes that the physical property of material with low resistance coefficient still be able to be maintained in substrate process and device use.
In order to reach the highest circuit density, the thickness of metal layer with low resistance coefficient has to be reduced in the circuit structure. But in the process, it shall be careful to avoid damaging those thin layers. The damaged thin layer will cause the poor circuit structure and increase the rejected rate of substrate. The growth of film and etching of circuit can be achieved by the plasma technique generally. The etching process is apt to damage the thin layer. The plasma can be used for strengthening the effect of etching. However, maintaining the steady plasma will cause the increase of ions impacting the substrate surface, and damage the circuit on the substrate.
Therefore, it is necessary to provide a plasma processing device and plasma processing method thereof, in order to improve the damage of chip or wafer by the plasma processing device.